Skip to main content

Questions tagged [qgis-3]

for questions specific to the 3.x series of QGIS.

Filter by
Sorted by
Tagged with
0 votes
0 answers
26 views

Getting raster local pixel coordinates from lat/lon coordinates in PyQGIS [closed]

I am tasked with the development of a plugin for QGis (QGis 3.36 Maidenhead) via the python PyQgis API. The plugin focuses on signal analysis of satellites images in GeoTIFF raster format. Once the ...
Federico's user avatar
1 vote
1 answer
41 views

QGIS Raster Calculater Syntax - unable to combine 2 expressions

I have a slope (in degrees) of a DEM where I'm attempting to assign various values to various bands via Raster Calculator. The individual expressions work, but when combined they do not. ("slope-...
IanGS's user avatar
  • 376
2 votes
0 answers
44 views

How to show / hide multiple symbols at once in QGIS?

In the layer panel of QGIS 3.34, it is possible to select multiple layers using either mouse drag or shift + arrow up/down and then press the space bar to show/hide them all at once. However doing the ...
nicolas galipot's user avatar
4 votes
2 answers
57 views

Change Value of Cell in Cost Layer (Raster) by whether it touches neighbouring cell

QGIS 3.36-Maidenhead: I have compiled a very large cost raster covering parts of Africa. I have applied cost values to all cells based on geographical considerations. I'd like to carry out a final ...
IanGS's user avatar
  • 376
0 votes
1 answer
23 views

Empty Metadata table in Semi-Automatic Classification Plugin of QGIS

I am working on Landsat 8 images using QGIS 3.36.2 When I want to convert clipped images to reflectance in Semi-Automatic Classification Plugin, nothing is displayed under the metadata table even ...
chandanr777 's user avatar
3 votes
1 answer
104 views

How to stretch an image into polygon symbology on QGIS?

I have a world map polygons (vectors) on QGIS 3.28, and i want to add flag on each country. I have already a svg flag for each country on a field, but flags are represented like a mosaic: I try to ...
Rien Avoir's user avatar
0 votes
0 answers
20 views

Why does PyQGIS start saying roo.children() is empty after a while?

I am working on a small extension to the QgsProject Class. import sys sys.path.append("C:/Program Files/QGIS 3.34.6/apps/qgis-ltr/python") from qgis.core import (QgsApplication, QgsProject, ...
Bendigo McAllan's user avatar
0 votes
0 answers
26 views

Qgis2web hyperlink on polygon

I would like to create an interactive webmap with the function that each point, line, and polygon, when clicked, will be redirected to a specific URL website. Is there any way I can do that in ...
Vlademir Sazon's user avatar
0 votes
1 answer
26 views

Point Cloud Processing Tools on MacOS

I am trying to access the native Point Cloud Processing tools, developed by Lutra Conslting and added to QGIS 3.32 (https://www.lutraconsulting.co.uk/blog/2023/05/30/pointcloud-qgis-processing/). I ...
SamH's user avatar
  • 1
1 vote
0 answers
44 views

Opening network folder in Windows file explorer using QGIS

Among the attributes of a layer, I have a "PERCORSO_CARTELLA_SP" field that points to a SharePoint network folder. In QGIS 3.28.15, I can open the folder with Win10's file explorer using the ...
VadoDeCorsa's user avatar
0 votes
1 answer
22 views

Saving a vector layer with a different projection in the same directory as the original layer

I have a vector layer and I want to save it in the original directory, but I can't because access to the source file is denied. projekcia_prj = QgsCoordinateReferenceSystem("EPSG:3857") ...
Stano's user avatar
  • 41
0 votes
0 answers
24 views

Set your own QGIS plugin folder

In QGIS 3.32 I would like to deactivate the path to the plugin folder in the user profile. The plugins should be managed centrally (company instruction), without the user being able to add new plugins ...
cc_schr_gis's user avatar
0 votes
1 answer
40 views

QGIS Script - Use the results of a child algorithm

I want to create a script that runs native:pointsalonglines as a child algorithm and then does some other things with the results. But the moment I use getFeatures() in the results of the child ...
Daniel Möller's user avatar
0 votes
1 answer
40 views

List all selected layers in PyQGIS

I would like to list all the selected layers in the QGIS Layers Panel with PyQGIS. I'm looking for a PyQGIS function returning a list of all selected layers or a method to check if a layer is selected....
LeoC's user avatar
  • 547
1 vote
0 answers
33 views

Can't Import NAD83 / NRCan LCC Canada (EPSG:42304) in QGIS

I need to define the NAD83 / NRCan LCC Canada (EPSG:42304) CRS in QGIS to use the NBAC wildfire data from https://cwfis.cfs.nrcan.gc.ca/datamart/metadata/nbac. Since QGIS does not recognize this CRS I ...
JForsythe's user avatar
  • 173
0 votes
0 answers
21 views

Blue cross in middle of QGIS map canvas - how to remove? [duplicate]

QGIS has started putting a blue cross in the middle of the map canvas. I've seen earlier posts where this was found to be caused by a plug-in, and disappeared after the plug-in was updated. However, I ...
David Johnson's user avatar
0 votes
0 answers
18 views

Problem with rasterize vector layer to raster

I am trying to rasterize a vector layer by the rasterized tool for an university project (QGIS version 3.36.1). My lecturer did it without entering a burn-in value (because it is optional) and just ...
Lou190's user avatar
  • 1
0 votes
0 answers
43 views

PyQGIS - zoom/fit layer extent to map item layout extent

I have a temporary vector file from a qgis processing.run() (basically a line shapefile temporary output): gis_osm_roads_free_1_lyr = results['Gis_osm_roads_free_1'] I have a map_item: map_item = ...
Marin Marian's user avatar
0 votes
0 answers
38 views

Changed project from QGIS 3.16 to 3.24, now 'NULL' fields turn into '-9223372036854775808'

Been working on a digitizing project on QGIS 3.16.15-Hannover, as I like to use LTR versions for the stability. But, 3.34 introduced an automatically incrementing UUID field, which I find useful. My ...
Nelg's user avatar
  • 175
1 vote
1 answer
33 views

Expression to auto-fill field according to the order of polygon creation

I'm working on an urban cartography actualization project, looking for a way to auto-fill a field (let's call it "field_1") in the new polygons created in the buildings layer. I need to ...
Mig TabSher's user avatar
2 votes
1 answer
47 views

QGIS layout, print grid labels beside lines

I am using QGIS (v3.36.1) to make a map for planning purposes. For the layout, I am looking at a map made in some kind of CAD software. It has labels on the gridlines inside the border, which I can ...
MortenSickel's user avatar
  • 3,824
0 votes
0 answers
18 views

QGIS crash everytime post not saving new layer

I edited one layer but closed project without saving it. Now my project is opening but it crashes within 2 - 3 minutes' of opening. What all I can do to save my work?
Rahul Raj's user avatar
1 vote
1 answer
77 views

Calculating field using expression taken from DataFrame with PyQGIS

The sample data can be downloaded here: https://github.com/jude9apple/sampleData I am using PyQGIS in QGIS 3.36 (in PyCharm) to run a script which reads a table containing which processes apply to ...
Juliette Lapeyre's user avatar
1 vote
0 answers
47 views

WMS layer doesn't load using PyQGIS

I'm using the following code to load a WMS layer to QGIS : url = "https://data.geopf.fr/wms-r/wms?SERVICE=WMS&VERSION=1.3.0&REQUEST=GetMap&STYLES=normal&FORMAT=image/geotiff&...
aogino's user avatar
  • 13
0 votes
0 answers
45 views

Semi-Automatic Classification plugin error - QGIS - failed dependencies

I had been using SCP for the last year and just recently it stopped working. If I run any process that generates new images, those images are empty (all no data). I tested the dependencies and got: -...
rodrikev's user avatar
  • 500
0 votes
0 answers
24 views

QGIS Issue: Empty Tables When Styling or Adding Features

When using QGIS, I encounter empty tables when attempting to style features or add polygons to layers. This happens consistently across different functions.
Iacobet Iulian's user avatar
0 votes
0 answers
40 views

How to clip satellite base map into polygons [duplicate]

I'm trying to create a model to detect trees within the boundary of a country in QGIS 3.34. So far, I'm using the Google Maps Satellite base map from QuickMapServices. I created a vector layer where I ...
Bartek's user avatar
  • 9
0 votes
0 answers
46 views

QGIS: How to speed up loading of relation in forms

In QGIS I have two layers: layer containing points (trees) that each have an specific ID table contains all survey data. Each survey also contains the specific ID of the tree I linked them via the ...
Alexander Halm's user avatar
-1 votes
1 answer
35 views

Moved QGIS 3.6 to new PC and now need to change Output folder and Scripts folder

I moved my old QGIS to a new PC. Installed from zero, and later just copied "C:\Users[User]\AppData\Roaming\QGIS\QGIS3\profiles". Everything works fine, when I open my old projects it's all ...
Filip Frankopan's user avatar
0 votes
0 answers
29 views

Imported CSV files from Fieldmove and QGIS only displayed as lists

Downloaded some .csv data for an assignment I need to do (from fieldmove specifically), and am trying to display a single point for which i downloaded said data as a csv. file. However, when i try to ...
That Rock Guy's user avatar
0 votes
0 answers
53 views

Version error on SAGA NextGen on QGIS and MacOS

I am trying to use SAGA NextGen on QGIS and when I try to run a program I get an error message saying that I need to update the SAGA binaries to 9.1. I am using QGIS 3.34 on MacOS. Is there any way ...
ddomizia's user avatar
  • 648
1 vote
1 answer
41 views

In QGIS, a joined layer is not automatically set to edit mode, when edit mode of parent layer is switched on

I joined some fields of a different layer in QGIS (version 3.34.5) via layer properties, set them to editable and added them to the attribute form of the parent layer. However, when I use the form ...
ENOTTY's user avatar
  • 111
1 vote
0 answers
51 views

Calling ST_IsValid on a QgsGeometry in PyQGIS, referencing PyQGIS object in SQL statement

I'd like to be able to verify the validity of a geometry of type QgsGeometry within PyQGIS. From what I can understand, the steps are Convert QgsGeometry to something that ST_IsValid will recognize. ...
nr_aus's user avatar
  • 3,566
0 votes
0 answers
22 views

I am calculating LST for Mumbai

I am calculating LST for Mumbai and I found that only Airport and Slum, Barrel land is having high LST than any other region. I need to analyze it more if its just showing all area cooler in city like ...
kalpanapardeshi's user avatar
1 vote
1 answer
88 views

Meaning of error message on QGIS start-up

On start up QGIS 3.36.1 on Windows 10 I get this weird error message: 2024-03-25T12:10:17 WARNING Traceback (most recent call last): File "C:\Users/Kurt/AppData/Roaming/QGIS/...
Kurt's user avatar
  • 7,107
5 votes
1 answer
113 views

Getting list of intersecting layers into a field in a polygon table

I have a polygon layer with many other layers (different geometry but no points) in a map and I'd like to return the actual layer names where any object intersects with my polygons into a comma ...
RBCMark's user avatar
  • 397
1 vote
1 answer
131 views

Meaning of light-blue cross on map-canavas

What is the meaning of this light blue cross sign on the map canvas of QGIS? I upgraded from 3.34 to 3.36 and now I see this cross sign, when opening a new blank project and also on some, but not all ...
Kurt's user avatar
  • 7,107
1 vote
1 answer
28 views

Expression Builder using times

I have brought in vector layer from a .csv file containing Total Response Time for Emergency Services Incidents. While the times are in HH:MM:SS format I believe that having brought it in as a .csv ...
Mark Leander's user avatar
1 vote
0 answers
54 views

QGIS crashed when exporting from map layout

I am a self-taught QGIS user, and I am making a map of the nature preserve where I work. I was practically finished with the whole project when I ran into this problem. Every time I go to export the ...
Madeline Cox's user avatar
2 votes
0 answers
27 views

pyqgis - Show layer properties in layer name in a same way as feature count [closed]

Setting 'Show Feature Count' adds a number of features in layer's name, but doesn't actually change its name, in a sense that its name can still be got from the 'name()' method and the result would ...
ViperMiniQ's user avatar
1 vote
1 answer
38 views

QGIS Export ESRI File Geodatabase versus ESRI FileGDB

Ive just noticed in QGIS (v3.28.11) that on the "Save Vector Layer As" format options, that there are two ESRI File Geodatabase options. One is called ESRI File Geodatabase The other is ...
nr_aus's user avatar
  • 3,566
0 votes
1 answer
36 views

Using PyQGIS to iterate through layers with custom layout

How do I select the layer and apply a layout for export to .PNG? I use: QGIS 3.34 and the Python Console. So the manual process is: select layer => go to Layout Manager => Select Layout => ...
Cerveser's user avatar
  • 101
0 votes
1 answer
42 views

Retain QGIS window layout

Is it possible (in QGIS 3.16) to retain the layout of windows. So whenever I open the project it opens as below? Critically the Attribute table in Form view with the Pan option on the RHS and a ...
GeorgeC's user avatar
  • 8,238
0 votes
0 answers
32 views

Limiting the shown area for a shapefile

I am new to QGIS so im not that experienced with the program. I want to create a GeoPackage with various WMS and shapefile information sources for a small area, but all my source files have displayed ...
Student M's user avatar
0 votes
0 answers
27 views

Supressing algorithms messages in custom processing algorithms log

I would like to provide clean feedback in processing algorithms log, but it is full of intermediate algorithms results, which are cryptic and needless for user: Is there a way to suppress these ...
Kubson's user avatar
  • 614
1 vote
0 answers
32 views

"ERROR: Incomplete GRASS session: Variable 'LOCATION_NAME' not set" while running r.covar in QGIS

QGIS version: 3.34.3-Prizren QGIS code revision: 47373234ac Qt version: 5.15.3 Python version: 3.9.18 GDAL version: 3.8.3 GEOS version: 3.12.1-CAPI-1.18.1 PROJ version: Rel. 9.3.1, December 1st, 2023 ...
GiorgosK's user avatar
0 votes
1 answer
64 views

Node information in a PostGIS dataset

I am working in QGIS / PostGIS to plan the cable layout for a seismic array. The power distribution is from the green point with the white cross in the middle. The nine green points marked with a ...
MortenSickel's user avatar
  • 3,824
0 votes
1 answer
35 views

I can't seem to overlay maps with a transparent background in the map layout like I used to

I have a workspace that I created maybe a year ago that was an evolution of a workspace I've used since before version 3, where I have 3 maps elements in a layout stacked in an overlay (to keep them ...
willemite's user avatar
  • 118
1 vote
1 answer
30 views

QgsVectorLayer not loading correctly

I'm working with PyQGIS and have encountered an issue. While my code successfully creates a new layer (as evident in the screenshot attached), this layer does not load correctly into the project. I'm ...
Diogo Barros's user avatar
0 votes
1 answer
49 views

How to display an image in a UI custom form created with QtDesigner in QGIS 3.28

I created a custom form with QtDesigner. For the image in the form I used a QLabel and added the path of the picture to the "pixmap" attribute. The path is C:\Users\Dennis\Desktop\Formulare\...
Dennis's user avatar
  • 43

1
2 3 4 5
89